Magnetic impedance sensors of a detection coil output type are widely known in the art and used in various fields as magnetic sensors that can measure the magnetic strength with a high degree of accuracy and high responsivity.
Amorphous wires of Co-based alloy are used as magneto-sensitive bodies of the magnetic impedance sensors. Conventionally, such wires have been manufactured using an in-rotating liquid spinning method, for example, as described in Patent Literature (PTL) 1. The in-rotating liquid spinning method, which is a method of manufacturing a thin metal wire in an amorphous state, includes blowing molten metal from a nozzle by gas pressure into a centrifugally-held coolant on the inner wall of a rotating drum and thereby rapidly cooling and solidifying the molten metal. For the use as the previously-described magneto-sensitive wire, it is required for the manufactured wire to be worked into a targeted wire diameter for stabilization of the output and to have appropriate magnetic characteristics suitable for the magnetic field to be measured. The manufactured wire is therefore used as a magneto-sensitive wire for a magnetic impedance sensor after being subjected to a wire drawing process, such as using a die or dies, and heat treatment for ensuring the targeted magnetic characteristics.